How to Combine Separate WordPress Themes

1. Open the folders containing each theme's files. Choose the aspects of each theme that you want to combine, based on the files available. These files are header.php for the top header of the site, sidebar.php for the sidebar and footer.php for the footer. Note that there may be more than one sidebar file. The rest of the files hold the content area, including search pages, archive pages and comments area. Decide which theme's content area you want to keep; this will be the base of your new theme. Rename this folder so that you don't forget this.
2. Copy whichever header, sidebar, and footer files from the other theme you want to combine with your new base theme.

3. Open each of the files you copied in a text editor. Make a note of the names of each of the elements in this file, including the IDs of all
tags.
4. Open the style.css file in the folder from which you copied these files. Go through the file and delete any section that is not contained in the files you just moved. For example, if the footer.php file calls
and
, keep these sections, plus any section that references them; for example, keep footer.img if it is present.
5. Copy everything that is left in the style.css file, and paste it into the style.css file of your new theme. Scroll right to the bottom and paste it on a new line.